Depending on your budget I would start with the following
If you have not already done so - Upgrade your coax connection from the DAC to your Preamp/component system. You will be amazed at what an improvement in the sound you will get. Pangea Audio Premier XL Digital Cable with Cardas Copper - is a good option for the money.
Another option is to upgrade your DAC to one with a newer DAC chipset
for example - the auralic altair g1 ( with the ESS 9038Q2M chipset) - would replace the Node 2i and the mytec DAC.
If you have not already done so - Upgrade your coax connection from the DAC to your Preamp/component system. You will be amazed at what an improvement in the sound you will get. Pangea Audio Premier XL Digital Cable with Cardas Copper - is a good option for the money.
Another option is to upgrade your DAC to one with a newer DAC chipset
for example - the auralic altair g1 ( with the ESS 9038Q2M chipset) - would replace the Node 2i and the mytec DAC.